SWP Solar Wind & Interplanetary Medium

Question 1

The Parker spiral describes:

Accepted Answer

The Archimedean spiral shape of the interplanetary magnetic field resulting from solar rotation and radial solar wind flow

Answer

The helical path of solar energetic protons to Earth

Answer

The spiral structure of solar flare ribbons

Answer

Coronal hole rotation patterns

Question 2

At 1 AU, the average solar wind speed is approximately:

Accepted Answer

400–500 km/s

Answer

100–200 km/s

Answer

800–1000 km/s

Answer

1500–2000 km/s

Question 3

A corotating interaction region (CIR) forms when:

Accepted Answer

A fast solar wind stream from a coronal hole runs into and compresses the slower ambient solar wind ahead of it

Answer

A CME overtakes the ambient solar wind

Answer

Two CMEs interact in the interplanetary medium

Answer

Solar wind density doubles during solar maximum

Question 4

The southward component of the interplanetary magnetic field (Bz) is critical for geomagnetic activity because:

Accepted Answer

Southward Bz enables magnetic reconnection at the dayside magnetopause, transferring solar wind energy into the magnetosphere

Answer

Southward Bz increases solar wind pressure

Answer

Southward Bz is associated with CME arrival at Earth

Answer

Southward Bz directly increases radiation belt electron flux

Question 5

The L1 Lagrange point (~1.5 million km sunward of Earth) is the preferred location for space weather monitors because:

Accepted Answer

It is gravitationally stable and provides ~15–60 minutes of advance warning before solar wind structures reach Earth

Answer

It has direct line-of-sight to all solar active regions

Answer

L1 is inside the magnetosphere, giving real-time magnetospheric data

Answer

Solar wind speed is fastest at L1

Question 6

Solar wind density enhancements called 'heliospheric plasma sheets' crossings are associated with:

Accepted Answer

Sector boundary crossings of the heliospheric current sheet, linked to enhanced geomagnetic activity

Answer

Increased solar energetic particle flux

Answer

Elevated cosmic ray flux at Earth

Answer

High-speed stream interfaces only